Intestinal polyps are protruding lesions of the intestinal epithelium, occurring chronically in the intestines. The number of polyps ranges widely from 1 to 100 or more depending on the underlying condition. Pathologically speaking they include a variety of lesions ranging from benign neoplastic lesions to malignant neoplastic lesions, including hyperplastic lesions, dysplastic lesions, adenomas and adenocarcinomas. Particular worrisome from a clinical perspective is the fact that when a lesion exceeds 1.5 cm in size it may turn malignant, eventually becoming the base of a colonic tumor. Consequently, intestinal polyps are removed endoscopically by polypectomy or the like using a colonoscope. However, endoscopic surgery using a colonoscope is time-consuming and burdensome for the patient, and cannot generally be called an entirely satisfactory treatment. Moreover, patients with familial adenomatous polyposis (FAP) or adenomatous polyposis coli (APC), a high-risk group for colon cancer, commonly suffer from 100 or more intestinal polyps, and these polyps can become cancerous. Consequently, such patients may have no choice but to undergo total colonectomies while still young in order to prevent intestinal cancer.
At present the only known treatment for intestinal polyps is the endoscopic surgery discussed above, and no drugs are known that are aimed at suppression. That is, no drugs are known for treatment and/or prevention (suppression of occurrence). Research has just begun on such drugs. There is demand in the art for a drug that would be effective in inhibiting the occurrence of such intestinal polyps.
The inventors have long dedicated themselves to research aimed at providing effective drug components. In the process of this research, we discovered previously that a series of carboxylic acid amide compounds are useful as anti-inflammatory drugs and calcium antagonists, and perfected an invention based on this finding (Japanese Patent Application Laid-open No. S61-151199). We later discovered that another group of carboxylic acid amide compounds with a similar framework have excellent lipid-lowering ability and are useful in the prevention and treatment of hyperlipidemia, and perfected an invention based on this finding (Patent #2584336, Specifications). We also discovered within this group of compounds a new compound that acts on urinary protein excretion and is effective for treating nephritis, and perfected an invention based on this finding (Japanese Patent Application Laid-open No. H10-265387). In addition, we discovered that this compound which is useful as a nephritis treatment agent also has a separate effect of lowering neutral lipids (triglycerides, TG), total cholesterol and the like, in the liver, and is useful as an agent for preventing and treating fatty liver (Japanese Patent Application Laid-open No. H11-302178).